For light weight, excellent abrasion resistance, strong toughness and other excellent performances, composites are adapted to wide engineering requirements, and the specific strength, the specific modulus and the heat resistance of the composite materials are superior over those of the matrix metals, therefore playing an important role in the development of advanced technology fields such as aerospace, and attracting worldwide attention increasingly. Three-dimensional weaving technology is called one of the most advanced manufacturing technologies for composites worldwide at present. Internationally, load-bearing beams and joints in various shapes in devices such as aircrafts and automobiles have been manufactured successfully by the three-dimensional weaving technology for composites. With such technology, artificial bones, artificial ligaments and bone fracture plates and the like have even been manufactured in the terms of artificial biological tissues. In recent years, with the rapid development of the aerospace industry and the national defense industry or the like in China, requirements on the weaving technology for composites have been higher, and the demand of manufacturing bearing structure parts by the direct forming of composite materials becomes higher.
Products made by the traditional two-dimensional layered weaving equipment have some disadvantages which is hard to overcome: for example, the overall structure of the product is simple, both the rigidity and the strength in the thickness direction are low, the strength of in-plane shear and inter laminar shear is low, it is easy to delaminate, and both the impact toughness and the damage tolerance level are low, so that they cannot meet the performance requirements of main bearing structure parts. In recent years, the developed countries have been committed to develop novel weaving equipment to realize mass production of three-dimensional weaving preforms. In 1971, General Electric in the United States invented a three-dimensional weaving machine named of ‘Omniweave’. From then on, weaving machines have been developed in the trend of mechanization, automation and micro-computerization, and CAD/CAM integration was realized initially. The North Carolina State University in the United States developed a full-automatic continuous yarn-feeding weaving machine, which is the first full-automatic weaving machine in the world. In China, relevant researches on the optimization and improvement of three-dimensional weaving process and weaving equipment have also been carried out. The Tianjin Polytechnic University, the Nanjing University of Aeronautics and Astronautics, the East China Institute of Technology and the National University of Defense Technology and the like have developed three-dimensional weaving machines, some of which can three-dimensionally weave the products in relatively simple shape. However, the working efficiency is low, and there is still a pronounced gap compared with the advanced level in the world. And most three-dimensional weaving machines are obtained by modifying the traditional looms.
Although products woven by the existing advanced three-dimensional weave-forming equipment at home or abroad have been greatly improved in aspects of structure shape, delimination and mechanical property and the like, there are still the following shortcomings: (1) the structure of products made by the equipments is still simple, and for preforms with complex shape, it is necessary to change the layout or quantity of fibers during weaving, resulting in that the processing procedure is complex, and it is hard to realize automation control; (2) the existing advanced three-dimensional weave-forming equipment are not suitable for processing preforms with large dimension; (3) the effect of dipping fibers with resin is not so ideal and the porosity is high, and as a result, the mechanical property, the weather resistance and the fatigue life of products are decreased.